Juliana Freire Maya Ramanath Lingzhi Zhang A Flexible Infrastructure for Gathering XML Statistics and Estimating Query Cardinality. 857 2004 conf/icde/2004 ICDE http://doi.ieeecomputersociety.org/10.1109/ICDE.2004.1320085 db/conf/icde/icde2004.html#FreireRZ04